The grade drop came in July after his work was cross marked for the first time in two years.

Cross marking, where work is marked by a different teacher, is carried out at schools to ensure the grade awarded to each student is an accurate reflection of their work.

Now more parents, and students, have come forward saying the marking bungle in an English subject was more widespread than one student.

The State Government's Education Department has not explained how the situation came about or what has been done to stop it happening again.

Parents desperate for answers, and options, say they have been stonewalled by the school, and department, which continues to claim it is doing all it can to rectify the situation.

A letter signed by the school's principal addressed to parents and guardians, states "a small group of students" had been impacted by the mistake.

Not all parents of the affected students received a copy of the letter.

A parent who contacted the QT says there were about 15 students facing similar circumstances to the student highlighted in last week's story.

Some of those students have also contacted the QT.

All have asked for anonymity to protect their privacy and avoid the stress of being named publicly after the devastation of realising finishing school with a Year 12 certificate may not happen.

The parents say; the school delayed informing parents, 'corrected' report cards sent out were still incorrect, tutoring offered to help the students has been inconsistent, frequently cancelled, and when not cancelled, it wasn't unusual for no one to arrive to teach the class.

For one student, the shock of having their marks suddenly downgraded has led to a serious depression.

Another student, whose mark was also dropped from a B to a D, said even after trying to catch up, they were still given a D with only five weeks left until the term ends.

In 2015, 20% of the senior students at Bundamba Secondary College went on to study university, according to the MySchool website where the 2015 figures are the latest available.

The latest NAPLAN testing results for 2016 show the school's performance is "substantially below" the national average, in every field.

The school's NAPLAN performance also falls short of the results at other, similar schools.

Yesterday, the Department said the matter has been investigated by the school and extra tuition offered to the affected Year 12 students with concerned guardians encouraged to contact the principal.

"Eligible students have also undertaken alternative assessments as permitted under Queensland Curriculum and Assessment Authority provisions," a department spokesperson said.

What we asked

The QT verbally asked the Department how many students had been affected and put these questions in writing, offering three opportunities to answer;

Is cross marking standard practice? If so, how can a student's work go un-cross marked for two years?

How does Education Queensland respond to claims (the school had not provided an adequate explanation nor viable options to rectify the situation) and does it consider this acceptable?

Can Education Queensland assure the rest of the students, particularly Year 12s, they have not been misled on the marking standard?